Orthesis with multiple hinge

ABSTRACT

An orthopedic device comprises: a structure comprising two substantially rigid parts, for instance a rod, which parts are coupled to each other by means of hinge means and each comprise fastening means for optional temporary fastening to a limb part, wherein a pivot axis of the hinge means extends at least more or less in the region and in the direction of the pivot axis zone of the relevant joint. The device according to the invention has the feature that the hinge means comprise two hinges, the respective pivot axes of which extend in directions which make an angle with each other of 90°±40°, or preferably 90°±20°.

The invention relates to an orthopaedic device, in particular aprosthesis or an orthosis, for the purpose of replacing respectivelysupporting the function of at least one part of a human limb with apivotable joint, for example a leg with a knee or an arm with an elbow,on either side of which joint there extend respective limb parts, suchas a lower leg and an upper leg respectively a lower arm and an upperarm, which device comprises:

a structure comprising two substantially rigid parts, for instance arod, which parts are coupled to each other by means of hinge means andeach comprise fastening means for optional temporary fastening to a limbpart,

wherein a pivot axis of the hinge means extends at least more or less inthe region and in the direction of the pivot axis zone of the relevantjoint.

Such a device is known from for instance U.S. Pat. No. 5,792,086 andGB-A 2 099 309.

An orthosis is an assist means for supporting a limb with a reducedfunctionality and can be applied for instance with a paralysed leg. Anorthosis consists generally of at least two parts. First of all thereare components which stabilize a body joint such as an elbow or an anklein one or more directions. Such a hinge part generally has one fixedpivot axis.

A first problem of known orthoses is that the construction of anorthosis generally takes place on the basis of a positive plaster modelof the shape of the limb in a resting and non-loaded position. Owing toload and to movement the shape of the limb changes, for instance theangle between lower leg and upper leg in the frontal plane. It is theobject to mimic the loaded position by manipulating the plaster model,whereafter the construction of the orthosis takes place on the basis ofthis thus manipulated plaster model. The results of such a manipulationare however not readily predictable, which results in the orthosishaving to be corrected afterward, which is difficult andlabour-intensive. For this reason the correction is not carried out insome cases, which results in a non-optimal orthosis for the user. Asecond problem of known orthoses is that a rotation is generally onlypossible about one fixed main rotation axis of the orthosis whichgenerally corresponds with the characteristic rotation axis of the jointfor stabilizing. The characteristic rotation axis makes possible thecharacteristic movement of a limb, for instance flexing of a knee. Inthe case of a non-impeded bending of a limb however, the rotation axisof the relevant joint will generally also change direction. This knownproblem is addressed in the above stated two publications. An orthosiswith a fixed main rotation axis therefore obstructs the movement of therelevant joint and the associated limb parts. This obstruction resultsin undesirable stresses on the joint and the limb parts.

With a view to the above, the invention provides an orthopaedic deviceof the type stated in the preamble which has the feature that the hingemeans comprise two hinges, the respective pivot axes of which extend indirections which make an angle with each other of 90±40, preferably90±20.

The pivot axes can intersect in the manner of a cardan joint. In apreferred embodiment however, the device according to the invention hasthe feature that the pivot axes are located spatially at a mutualdistance, which distance is chosen such that it corresponds with thepivoting characteristics of the relevant joint. The best possible matchcan hereby be realized with the pivoting characteristics of the relevantjoint.

A preferred embodiment of the device according to the invention ischaracterized by bounding means for limiting to a chosen angularposition at least one of the pivoting movements of at least one of thehinges.

Owing to the stated measures the loaded position can be reached byrelative rotation of the orthosis parts without manipulation of theplaster model as discussed above, while the definitive position can bedetermined during use of the orthosis by adjusting the desired anglewith the bounding means adapted for this purpose, whereby a result thatis optimal for the user can be achieved in simple manner, without thelater correction required in the known orthosis.

A second advantage of the measures according to the invention is thatthe rotation of the orthosis according to the invention correspondsbetter to the natural rotation of the joint in question, therebyremoving a significant limitation in the movements of the relevantjoint.

Specified for this purpose is a device according to the invention withbounding means for limiting the pivoting movement of a hinge to a chosenangular position. Such a device can advantageously have the featureaccording to the invention that the fastening means comprise at leasttwo divisible rings with adjustable periphery, one of which is connectedto the one part and the other to the other part, and the bounding meanscomprise a flexible, tensively strong element, for instance a strap orcord, of optionally adjustable length, the ends of which are connectedto these rings such that the flexible element can bound the pivotingmovement of at least one hinge.

It will be apparent that the flexible element has to positioned at asuitable location relative to the hinge in question, and must generallyhave an at least substantial distance therefrom.

Alternatively, the device can have the feature that the bounding meanscomprise stop means added to a hinge.

The orthoses known from the two cited publications have a hinge part oneither side of the relevant joint. Such orthoses can be referred to asdouble-sided orthoses. According to the invention the device canadvantageously have the feature that said structure is provided on onlyone side with hinge means. Better cosmetic results are possible withsuch a device, which is found to be greatly valued by users duringtests. Furthermore, with a single-sided orthosis the construction of themultiple hinge according to the invention can be simpler than in thecase of a double-sided orthosis.

Two applications of the device according to the invention can be pointedto as important embodiments. In the one embodiment the device has thespecial feature that the device is a knee orthosis. In the otherembodiment the device has the special feature that the device is aknee-ankle-foot orthosis.

The invention will now be elucidated on the basis of the annexeddrawings of several random embodiments, to which the invention is notlimited. In the drawings:

FIG. 1 shows a perspective view of a part of a knee orthosis accordingto the invention;

FIG. 2 is a front view of a knee orthosis in which the operation of theadditional hinge is shown;

FIG. 3 is a view corresponding with FIG. 2 of the orthosis arranged on aleg;

FIG. 4 is a front view of the single-sided orthosis according to FIG. 1,2, 3 in the situation where the user is also standing on the relevantleg and the bounding means limit lateral displacement to the drawnvalue; and

FIG. 5 shows an alternative embodiment of a two-fold hinge.

Corresponding components are designated in all the figures with the samereference numerals.

FIG. 1 show an orthosis comprising an upper rod 1 and a lower rod 2which are coupled hingedly to each other by means of hinge means 3.Hinge means 3 comprise an upper hinge 4 with a pivot axis 5 and a lowerhinge 6 with a pivot axis 7. The pivot axes 5 and 7 correspondrespectively with the usual pivoting movement of the knee and aswivelling movement substantially perpendicular thereto.

In order to fasten the orthosis 8 to the leg of a user, use is made oftwo sets of divisible rings with adjustable periphery, which inaccordance with FIGS. 2, 3 and 4 are designated respectively 9, 10, 11,12.

The rings 10 and 11 are connected to each other by means of a flexible,tensively strong element 13, for instance a strap or cord of optionallyadjustable length, such that this element 13 functions as limit to theswivelling movement of hinge 6 and allows the knee to move unhinderedover the free swivel zone. Reference is also made in this respect toFIG. 4 in which the flexible element in its tensioned position limitsthe lateral swivelling movement of said hinge 6. It is noted that it isnot necessary in all conditions for the bounding element 13 to besituated diagonally on the other side of rings 10, 11 in relation tohinge 6.

The orthosis 9 can for instance be used to support a knee which may onlybe loaded in a determined position rotated in the frontal plane, forinstance in the case of cartilage problems in the knee.

FIGS. 2 and 3 show the knee orthosis 8 in bent position in accordancewith the position of a leg wherein the lower leg makes an angle of forinstance about 90 with the upper leg. Particular reference is made inthis respect to FIG. 3. said swivelling of the lower leg takes place dueto the operation of hinge 4 and a rotation about pivot axis 5. For alateral displacement of the lower leg, as shown in broken lines, aswivelling takes place about pivot axis 7 of hinge 6. In this manner itis possible to effectively follow the desired movements of the knee, andthe functionality of the knee in question can be substantiallysupported. In FIGS. 2 and 3 in the position drawn in broken lines therelevant components are provided with reference numerals with an accent.

FIG. 5 shows hinge part 3 with the associated components on enlargedscale.

1-8. (canceled)
 9. An orthopaedic device, in particular a prosthesis oran orthosis, for the purpose of replacing respectively supporting thefunction of at least one part of a human limb with a pivotable joint,for example a leg with a knee or an arm with an elbow, on either side ofwhich joint there extend respective limb parts, such as a lower leg andan upper leg respectively a lower arm and an upper arm, which devicecomprises: a structure comprising two substantially rigid parts, forinstance a rod, which parts are coupled to each other by means of hingemeans and each comprise fastening means for optional temporary fasteningto a limb part, wherein a pivot axis of the hinge means extends at leastmore or less in the region and in the direction of the pivot axis zoneof the relevant joint, wherein the hinge means comprise two hinges, therespective pivot axes of which extend in directions which make an anglewith each other of 90°±40°; in that bounding means are present forlimiting to a chosen angular position at least one of the pivotingmovements of at least one of the hinges; and in that the fastening meanscomprise at least two divisible rings with adjustable periphery, one ofwhich is connected to the one part and the other to the other part, andthe bounding means comprise a flexible, tensively strong element, theends of which are connected to these rings such that the flexibleelement can bound the pivoting movement of at least one hinge.
 10. Thedevice as claimed in claim 9, wherein the pivot axes are locatedspatially at a mutual distance, which distance is chosen such that itcorresponds with the pivoting characteristics of the relevant joint andfurther wherein said respective pivot axes make an angle with each otherof 90°±20°.
 11. The device as claimed in claim 9, wherein the boundingmeans comprise stop means added to a hinge.
 12. The device as claimed inclaim 9, wherein said structure is provided on only one side with hingemeans.
 13. The device as claimed in claim 9, wherein the device is aknee orthosis.
 14. The device as claimed in claim 9, wherein the deviceis a knee-ankle-foot orthosis.